Tatiana Maslany put in some long days playing numerous roles in "Orphan Black," often acting all by herself in the BBC America series.

Maslany stars as Sarah, a woman who discovers she's one of several clones who look alike and share the same genetic makeup, even if they act nothing like each other.

Maslany used music to help define each of her various clone characters--see her playlist for uptight soccer mom Alsion below--but how did she actually appear as three clones talking to each other in the same room at the same time? Not easily.

In the April 13 episode, "Variation Under Nature," Sarah and her new clone mentors, Alison and easy-going genius student Cosima, got to know each other Alison's house. The scene involving the three of them lasted about two minutes, but it took about 17 hours to film, Maslany said.

"It was madness," she said. "It became easier as we did more throughout the series. But initially it was like, 'Holy crap' Yeah, it was crazy."

Maslany explained that the production used a special camera called a technodolly that memorizes its moves so that it can mimic past camera moves.

Maslany filmed that scene as one character, we'll say Sarah first, while wearing an ear bud so she could here someone speak the other clones' lines. She tried to keep clear where the other clones were supposed to be standing or sitting so she could look in the proper place as she did her lines.

The process of switching to another clone--including makeup, hair, costumes--would take about 1 1/2 hours, she said.

They would then shoot the scene again with her playing the second clone, Cosima for example. Maslany would have to match her sight lines with what she had done previously. Once they got a good take with her playing Cosima, they moved on to her playing Alison and would repeat the process all over again.

"It was insane," said, laughing. "It's such a technical nightmare and it's crazy to try to be present in that scenario. As an actor you want to be present and listen to the other person, but there's nobody else there.

"So the challenge for me was like not only remembering the technical kind of things I had to hit, but also trying to do a performance as well."

As I said earlier, music helped those perfomances. This week I have Maslany's surprising playlist of show tunes for Alison's character.

"I think Alison has always dreamed of being a performer," Maslany said in an email. "This just felt like her bag."